NEW YORK (Reuters Health) - Many older adults report being discriminated against due to their age, according to a new study.

One third of British people in their 50s and above said they had experienced age discrimination, researchers reported in the journal Age and Ageing. That included being treated with less courtesy or getting poorer service at restaurants and hospitals.

"We know from other work that many older people feel that they are discriminated against," lead researcher Isla Rippon, from University College London, said.

But these rates were surprisingly high, she added.

"Perceived day-to-day discrimination can affect both physical and mental health," she told Reuters Health. Frequent perceived discrimination may be a chronic source of stress and build up over time, leading to social withdrawal and reluctance to go to the doctor, Rippon said.

She and her coauthors analyzed questionnaires from a long-term study of more than 7,000 people age 50 and older who were living in England in 2003. The current data come from responses in 2010 and 2011.

Participants rated how often they experienced five discriminatory situations: being treated with less respect, receiving poorer service than other people in restaurants and stores, receiving poorer service in hospitals, being treated as not clever and being threatened or harassed.

They also specified why they thought such discrimination had happened.

One third of all participants attributed at least some of their perceived discrimination to age. That rose to 37 percent of those over age 65.

"About one third of the people report age discrimination in Europe and only about 17 percent report ethnic discrimination," Liat Ayalon, who studies older adults at the Bar-Ilan University School of Social Work in Ramat-Gan, Israel, said.

Ethnic discrimination tends to be studied more than age discrimination, she said, though that seems to be changing as the global population ages.

It's also important to keep in mind that perceived discrimination and actual discrimination can be two different things, Ayalon, who was not involved in the study, told Reuters Health in an email.

In the new study, working people were 25 percent less likely to report age discrimination than their retired counterparts, the authors write.

Older retired men with less money and more education were most likely to report age discrimination.

Better-educated people may be more attuned to inequities and more likely to report discrimination of any kind, Rippon said.

Seventeen percent of all participants - the highest proportion - reported being treated with less respect because of their age. Less than five percent said they had experienced age-related harassment.

"Of particular concern were the 10 percent of all respondents who felt that they had been discriminated (against) due to their age in health settings," Rippon said. "This provides further evidence for the existence of ageism in healthcare."

"For healthy, independent-living people the effect (of age discrimination) on health will be indirect," Wim van den Heuvel said. A professor of care science at the University of Groningen, the Netherlands, he did not participate in the new research.

Most of the people in this study were living independently.

People experiencing, or thinking they are experiencing, discrimination may go out less, feel sad or less safe, withdraw or become depressed, van den Heuvel told Reuters Health.

For older people not living independently, discrimination could actually lead to poorer medical care, he said.

Because this study lines up with results from the European Union and United States, the general findings about perceived discrimination probably apply to most countries, Rippon said. But the links to specific social factors like education and wealth may not.